Figure 3.

Effects of five iridoids on the productions of nitric oxide (NO), prostaglandin E₂ (PGE₂), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6). RAW 264.7 cells were treated with ASP, ASPA, DAA, SME, and CSME at the concentration of 40, 80, and 160 μg/mL, respectively, for 1 h, and then induced with 50 ng/mL LPS for 24 h. The levels of NO (A), PGE₂ (B), TNF-α (C), and IL-6 (D) in the cell-free culture were measured by ELISA. * p < 0.05, ** p < 0.01 and *** p < 0.001 versus LPS-only treatment group; ^### p < 0.001 versus control group (n = 3).